The invention relates to an improved apparatus for conveying granular material.
It is known to use screw type conveyors and belt type conveyors for conveying granular material from a location near the ground to an elevated position.
Screw type conveyors typically include an auger mounted within a tube. The auger typically has a diameter only slightly smaller than the inner diameter of the tube or channel. Rotation of the auger drives granular-material up the tube or channel to be discharged at an upper end. Screw type conveyors typical have high flow rates as the material is conveyed along substantially the entire cross-section of the tube. However, some granular materials such as fertilizer and sensitive seeds (i.e. peas, lentils, beans and canola), are susceptible to damage when conveyed in a screw type conveyor. Such damage results in reduced grade of the granular material and/or lower germination rates of the seed.
Endless belt type conveyors typically include an endless belt mounted in an elongated transport body. The belt is rotated to transport material up the transport body. Belt type conveyors cause significantly less damage to granular material than the screw type conveyors. However, the flow rate of this type of conveyor is comparatively lower than that of screw type conveyors.
The use of belt conveyors mounted in tubes is also known. Further, it is known to use augers mounted above such belts within intake feed hoppers of conveyors for assisting feed of material to be conveyed to the tube conveying portion of such conveyors. One type of such conveyor includes a tapered auger extending into the tube above the belt. However, having the auger member extend into the tube may limit the flow rate of the conveyor since a portion of the cross-section of the tube at the intake end is occupied by the auger. Further, the use of a single auger in a feed hopper is problematic since the single auger tends to load the belt on one side which may result in misalignment of the belt and damage thereto. In addition, the relatively large size required for a single auger increases the height of the intake hopper making it inconvenient to unload certain bottom dumping hoppers into the intake hopper. Further, the mounting of the auger such that it extends into the tube limits the ability to adjust the positioning of the auger in the intake hopper and does not provide the flexibility necessary to ensure positive clean out of the majority of the hopper. It also limits the ability to vary the size of the auger and, depending upon the material to be conveyed, damage may be caused by the auger to that material. Finally, the use of a single auger in the intake hopper promotes spillage since, as noted, a single auger tends to load the belt (and the intake hopper) on one side.
It is an object of the invention to provide an improved conveyor.
According to a broad aspect of the invention, the invention provides an apparatus for conveying material comprising an elongated tube having an input end and a discharge end; an intake hopper mounted at the input end of the tube; an endless belt passing through the intake hopper and elongated tube and returning to the intake hopper outside the tube, the belt being adapted to be rotated for transporting material from the intake hopper to the discharge end of the tube; at least two augers mounted in the intake hopper, positioned above the endless belt such that no portion of the augers extends into the tube; and drive means for driving the endless belt and rotating the augers; wherein rotation of the augers conveys granular material in the intake hopper toward the input end of the tube.
In one embodiment of the invention, the invention provides for the location of the augers in the hopper to be adjusted and facilitates easy removal and replacement of the augers. Further, the speed at which the augers are to be driven is adjustable. The foregoing provides great flexibility with respect to different applications which the conveyor will be used for. In another embodiment of the invention the augers are mounted at a fixed position above the belt.
The invention also provides for a conveyor having a low profile intake hopper. This facilitates use of the conveyor with bottom dumping hoppers, etc. which have little clearance for locating the intake hopper underneath. Where a low profile but high volume hopper is required, a wide hopper may be utilized in conjunction with additional augers located toward the rear of the hopper and adapted for moving material from the sides of the hopper towards the center where it will be transported by the belt and augers to the front end of the hopper and the input end of the tube.
Generally, the invention attempts to provide a conveyor with high flow rates by providing flood feeding of the conveyor at the point where the belt enters the tube. The conveyor of the present invention is also versatile in that the orientation, size and material of the augers and the speed at which they are driven may be changed depending upon the application for which the conveyor is being utilized.